X-ray Micro Computed Tomography Laboratory
The Computer Tomography (CT) Lab at the Australian National University, houses state-of-the-art equipment, including a high-resolution scanning electron microscope and a micro CT scanner. Both instruments are being used as crucial calibration tools for seal rocks to assess the sealing capacity of geological CO2 storage reservoirs.
The instruments can study core samples in super high-resolution in time and space at pore level under reservoir conditions, while being flooded with CO2. The CO2 can be pure or a more complex mixture matching commercial injection fluid compositions.
The electron microscope is being used to automatically image the mineralogy of core materials or cuttings at resolutions from a few microns up to several centimetres. It enables scientists to directly observe CO2 being trapped in reservoir rocks.
The high-resolution core scanning facility takes micro-scale (pore) measurements of geometries and processes, enabling dynamic imaging during CO2 flooding experiments. They can be compared to macro¬‐scale measurements of bulk petrophysical properties derived from Special Core Analysis (SCAL). The measurements can be used to calibrate the petrophysical properties between different scales (from pore to core scale) and enable the development of new algorithms to infer the petrophysical properties from pore scale to the entire reservoir (upscaling).
Key CCS Focus:
- This project aims to better quantity the efficiency of residual trapping, which is the trapping of CO2 within individual pores due to capillary forces.
- Quantifying residual trapping will assist storage operators to utilise the available pore space effectively and support their MM&V plans to reduce risk and inform regulators.
- Identifying the influence of various factors on residual trapping , including wettability, initial saturation and injection rate. A major focus is to use cross-scale imaging, modelling and experiment to construct better methods for upscaling these trapping efficiencies in heterogeneous formations such as laminated sands.